An overview from a vassal's perspective under their master.


An overview from a master's perspective over his or her vassals.

A Vassalage Agreement is an agreement between two civilizations, where one civilization swears fealty to another civilization, becoming their vassal. In exchange for protection against other civilizations, the vassal surrenders their political power, including their right to become Leader of the World Congress and United Nations and ability to declare war (they follow their masters into war).

Obtaining VassalsEdit

Vassals may only be obtained after entering the Medieval Era, and after a civilization has agreed to become your vassal. This agreement takes place in the Diplomacy Trade screen. There are two types of Vassalage: voluntary vassalage and capitulation.

Voluntary Vassalage is bought by the master during peacetime. There are several factors that civilizations take in order to voluntary be a vassal to a civilization:

  • Is the possible vassal at war? They are likely to seek masters for protection if they are badly losing in a war.
  • Is the potential master at war? They do not look for potential masters that are currently in war.
  • How many vassals does this civilization have? They are less likely to vassalize to a master that have many vassals to protect already.
  • Is the civilization powerful than them? They are more likely to vassalize to a civilization much greater in military might.
  • How far away is the civilization from the vassals? They are more likely to vassalize to civilizations closer to them.
  • What is their diplomatic attitude toward the civilization? They are extremely likely to vassalize to civilizations they fear!

Voluntary Vassalage also happens (forcibly) when a Civilization has brought another dead civilization back to life via liberating one of the dead civilization's former city.


Capitulation, also known as "forceful vassalage," comes after a civilization has been defeated in war. In exchange for allowing them to live, the vassal agrees to surrender to their captor. Capitulation provides a number of more benefits to the master. The surrendering civilization agrees to forgive most negative diplomatic relations with the master and is forced to remain their vassal until a number of conditions.

Ending VassalageEdit


Of course vassals may revolt against their master should their master not meet their terms of the arrangement, which is primarily protection!


They must take into mind that capitulated vassals will also revolt in cases of unsettling taxes!

Vassalage may be ended between two civilizations in a variety of ways. The master may choose to declare war on their vassal, immediately ending vassalage between them. The master may choose to liberate their vassal after being a master of the vassal for a specific amount of turns, immediately ending the vassalage agreement (but also providing a very large diplomatic modifier with them)!

The vassal may also request independence from the master. The master always has the option of accepting or refusing their request for independence. In both events, the vassalage agreement is immediately ended, but if a master refuses a request for independence, war is immediately declared between the two civilizations. Although voluntary vassals may request independence from their masters at any time after a specific period of turns, capitulated vassals have to resort to declaring independence and must meet the conditions below to do so.

Declaring independence from a master requires:

  • Vassalized for a certain amount of turns.
  • One of the following conditions:
    • Vassal has more cities than the master proportionally when vassalage started.
    • Vassal has more population than the master proportionally when vassalage started.

Benefits of VassalageEdit

Vassalage comes with a variety of benefits for the master.

  • Open Borders with the Vassal.
  • A free Diplomat is stationed in the Vassal's Capital Capital.
  • +20% of the Vassal's 20xScience5 Science, 20xCulture Culture, and 20xFaith Faith.
  • Double Master's Religious Pressure in Vassal's Cities.
  • +33% Tourism Spread to Vassal.
  • Vassal's ideology is always the master's ideology.
  • Levy a military from the vassal upon the master's era advance.
  • Vassal is ineligible to host the World Congress.
  • Ability to gather a portion of the Vassal's 20xGold Gold via taxes.

However, the master must pay a vassal maintenance fee in exchange for the variety of the benefits for the master and is based on the current vassal's overall maintenance to maintain the vassal's civilization.

Taxing VassalsEdit

Each vassal player in a team can be taxed at individual rates. This tax is available immediately after the vassalage agreement is made. All taxes are applied at the start of a turn. Taxes are deducted from the vassal's Gross Gold Per Turn and are divided evenly amongst the civilizations in the master's team (if there are more than one player). Vassal taxes can be set in intervals of 5% starting from 0% and ending in 25%. Taxes may only be set after a set interval

Heavily taxing a civilization will make them more likely to hate you and rebel against you when able to end vassalage.

Treatment of VassalsEdit

During a vassalage agreement, a master may see his or her vassals' opinion of their master. Their opinion can vary as it can be increase or decrease depending on the current incidents during the vassalage. These incidents could be:

  • Demands made of the vassals
  • Current taxation policy
  • Protection of their lands
  • Religious Interests
  • Current Trade Routes

Varying on the treatment given to the vassal, vassals may form an opinion which may inform the master that a possible revolution may incur or exist should they meet the conditions and might to get independence.

  • Content
  • Disagree
  • Mistreated
  • Unhappy
  • Enslaved